Helobdella Stagnalis Research Articles

The present state of leech fauna (Annelida: Hirudinea) in Dal Lake, Jammu & Kashmir, India

Dal Lake supports a diverse group of fauna, including fishes, aquatic birds, zooplankton, and macrobenthic invertebrates. This study is the first taxonomic documentation of the leech fauna of Dal Lake. A total of nine leech taxa belonging to four families were identified and described: Glossiphoniidae – Alboglossiphonia weberi, A. heteroclita, Glossiphonia complanata, Helobdella stagnalis, Hemiclepsis marginata asiatica, and Theromyzon sp.; Erpobdellidae – Erpobdella octoculata; Hirudinidae – Poecilobdella granulosa; and Haemopidae – Haemopis indicus. Leeches play key roles in prey-predator dynamics and host-parasite relationships in freshwater ecosystems and as bioindicators of water pollution. This study provides essential data for taxonomic accounts and the diversity of leech fauna in Dal Lake.

Seasonal variation, group/ solitary behavior occurrence and reproduction time of the predator leech Helobdella stagnalis (Hirudenia: Glossiphoniidae) in Sarchnar Stream/ Sulaymaniah Province, Kurdistan Region- Iraq.

Seasonal variation, group/ solitary behavior occurrence and reproduction time of the predator leech Helobdella stagnalis (Hirudenia: Glossiphoniidae) in Sarchnar Stream/ Sulaymaniah Province, Kurdistan Region- Iraq.

Molecular characterisation of leeches (Clitellata, Annelida) based on the mitochondrial cytochrome oxidase I (COI) gene region for Turkish fauna

ABSTRACT Leeches, classified under Hirudinea within the phylum Annelida, hold a crucial position within the aquatic ecosystem due to their substantial contribution to the intricate food web. As a result of some morphological and phylogenetic uncertainties in the classification, molecular studies have been implemented in leech taxonomy. We investigated the leech fauna in 14 wetlands in the province of Ankara in the Central Anatolia Region of Turkey between 2017 and 2019. A total of 38 specimens were collected from wetlands, representing two families, four genera, and five species (Glossiphonia complanata, Glossiphonia concolor, Helobdella stagnalis, Hirudo verbana, Limnatis paluda). Morphological characters were identified following examination under a stereomicroscope, and maximum likelihood (ML), neighbour-joining (NJ) and Bayesian inference (BI) analyses were employed to resolve the phylogenetic relationships using mitochondrial cytochrome c oxidase subunit I (COI). The haplotype analysis of the obtained COI region on 15 sequences revealed 11 haplotypes.

Abundance and composition of invertebrate-feeding leeches in relation to fish status in ponds

Leeches feeding on invertebrates are an important component of freshwater communities, including those dominated by fish, but the effects of fish on their abundance and distribution are not well explored. The relative densities and assemblage structure of two leech families, Erpobdellidae and Glossiphoniidae, were studied from May to August 2014 in ponds stocked with low biomass densities of young common carp Cyprinus carpio, too small to prey on leeches (low-fish ponds), and in ponds containing high biomass densities of large (one- or two-year-old) carp (high-fish ponds), using two types of activity traps (placed either on the bottom or near the water surface). The most common and numerous species were Erpobdella octoculata, Helobdella stagnalis, and Erpobdella nigricollis. The traps near the water surface captured relatively small numbers of leeches, yet the catches showed that in summer some of the leeches moved to the upper layers of the water column, which was free of macrophytes. No differences in leech species richness or diversity were found with respect to fish status of ponds; however, bottom erpobdellids were more abundant in high-fish ponds. Redundancy analysis identified the fish status of the ponds and total nitrogen concentration in water as the only significant variables explaining the distribution of leeches among ponds. Species distribution was nested, but the nestedness pattern was not affected by the fish status of the pond. While fish are generally believed to adversely affect macroinvertebrate diversity and abundance, our study shows that some predatory leech species can persist in the presence of fish and possibly indirectly benefit from it.

Karagöl (Sındırgı-Balıkesir) ve Gölcük Gölü (Bigadiç-Balıkesir) Hirudinea Faunası: Türkiye için Yeni Bir Kayıt

This study was carried out to determine the Hirudinea fauna in Lake Karagöl (Sındırgı-Balıkesir, Türkiye) and Lake Gölcük (Bigadiç-Balıkesir, Türkiye), which has not been found in any limnological studies before. It was determined the species of Placobdella costata, Helobdella stagnalis, Hirudo verbana, Haemopis sanguisuga and Dina punctata in Lake Karagöl and P. costata, Glossiphonia concolor, Dina lineata and D. punctata in Lake Gölcük. According to the findings of the present study, Dina punctata was reported for the first time in the Turkish Hirudinea fauna.

Causes for the High Mortality of European Green Toad Tadpoles in Road Stormwater Ponds: Pollution or Arrival of a New Predator?

Declining wetland areas cause many amphibian species to breed inside stormwater ponds (SWPs), which have been constructed alongside major roads to collect and retain polluted road runoff water. However, the suitability of such artificial ponds as a breeding habitat for amphibians remains unclear. Recently, a study found a very low survival rate of European green toad tadpoles (Bufotes viridis) inside SWPs, presumably because of high sediment pollution and/or the presence of a leech Helobdella stagnalis. To establish the effects of sediment pollution and leech presence on tadpole growth and survival, we exposed 480 green toad tadpoles to a number of controlled conditions inside holding tanks. We tested the following conditions: (1) ‘control’ (clean sediment + clean water); (2) ‘leech’ (clean sediment + clean water + leeches); (3) ‘SWP sediment’ (clean water + polluted sediment); and (4) ‘SWP sediment + leech’ (clean water + polluted sediment + leeches). Tadpole size and survival was monitored until metamorphosis and, individuals participated in swim tests and respirometry trials to the test potential effects of pollution on their escape capacity and metabolic rate. We found that the growth rate of tadpoles exposed to the SWP sediment (condition 3) was increased, while pollution had no effect on survival. By contrast, leeches heavily preyed upon tadpoles, leaving no survivors in conditions 2 and 4. Tadpoles swim speed and metabolic rate of toadlets did not differ between the ‘control’ and ‘SWP sediment’ group, the only conditions with surviving individuals. Our study found that leeches had the strongest effect on tadpole survival and were likely responsible for the low survival rates in SWPs observed recently. Hence, we suggest that adequate management measures are needed to limit leech penetration inside SWPs (frequent dredging/draining) to prevent these artificial structures from becoming an ecological trap for locally endangered amphibians but rather a base to help in their recovery.

Güney Doğu Anadolu Bölgesi Sülük Faunasının Araştırılması

Bu çalışma, Ocak 2012- Aralık 2014 tarihleri arasında Güney Doğu Anadolu Bölgesinde yer alan yedi ilde (Adıyaman, Batman, Diyarbakır, Gaziantep, Kilis, Mardin ve Şanlıurfa) bulunan akarsu, baraj, göl, gölet ve sazlık alan olmak üzere toplam 169 tatlısu habitatında sülük faunasının belirlenmesi amacıyla yürütüldü. Sülük örnekleri habitatın özelliğine göre birim zaman, birim çerçeve (Sülük toplama çerçevesi) ve Ekman kepçesi yöntemiyle toplandı. Toplam 169 sulak alanın 53’ünde sülük tespit edildi. Çalışma süresince toplanan sülük örnekleri su bulunan 0,5-1,0 L’lik pet bidonlarla laboratuvara taşındı. Sülük örnekleri önce % 10 etanol içinde bayıltıldı, sonra %70 alkol veya %4 formalin içinde tespit edildi. Toplanmış olan sülükler morfolojik özelliklerine göre stereo mikroskop altında teşhisi yapıldı. Bu çalışma sonunda , Güneydoğu Anadolu Bölgesi sulak alanlarında Albolossiphonia heteroclita, Albolossiphonia sp., Dina apathyi, Dina sp., Erpobdella octoculata, E. testacea, Erpobdella sp., Helobdella stagnalis, Hirudo sulukii, Placobdella costata ve Placobdella sp. olmak üzere altı soya ait toplam 11 farklı sülük türü belirlendi. Söz konusu çalışma kapsamında tesbit edilen H. sulukii dünya için 2016 yılında tanımlanmış bir tıbbi sülük türü olup, bölge halkı tarafından geleneksel ve tamamlayıcı tıp uygulamaları çerçevesinde kullanılmaktadır.

An overview of helminths of the European fire-bellied toad Bombina bombina (Amphi-bia, Anura) in the Volga River Basin

The helminthofauna of Bombina bombina (Linnaeus, 1761) has been studied to an unequal degree in different parts of the habitat. Thus, it has been studied in more detail in the west of its range (in the countries of central and eastern Europe) and in less detail in the center (in Belarus and Ukraine). There were few data on helminths of this host in the east of its range (in Russia). For the first time, an inventory of the helminthofauna in B. bombina was carried out for populations in the Volga River Basin. The results of our own research are presented and supplemented with information from other authors. We summarized scattered data on helminths from 390 specimens of amphibians collected over more than 40 years in the territory of five regions: Kaluga and Samara regions, the Republics of Mordovia, Tatarstan and Bashkortostan. The helminthofauna includes 21 species from three classes: Trematoda (15), Chromadorea (5) and Clitellata (1). For each species, we give the systematic position, localization, places of detection, geographical distribution and characteristics of the life cycle. The leech Helobdella stagnalis (Linnaeus, 1758) was first recorded in the European fire-bellied toad in Europe. Four species of trematodes are new to this amphibian species in Russia: Haematoloechus abbreviatus (Bychowsky, 1932), Paralepoderma cloacicola (Luhe, 1909), larvae, Tylodelphys excavata (Rudolphi, 1803), larvae and Astiotrema monticelli (Stossich, 1904), larvae. Another species of trematode – Strigea strigis (Schrank, 1788), larvae – was first recorded in this host within the boundaries of the Volga Basin. A specific parasite is the trematode Haematoloechus abbreviatus (Bychowsky, 1932). The number and composition of the species of helminths of the European fire-bellied toad vary in different regions; the structure of the helminth fauna is generally stable and includes three groups of species: adult and larval stages of trematodes, adult nematodes-geohelminths. The results of the study create a database for further population studies and contribute to the development of ideas about the distribution and formation of the amphibian helminth fauna in Europe, Russia and the Volga Basin.

An overview of helminths of the European fire-bellied toad Bombina bombina (Amphi-bia, Anura) in the Volga River Basin

The helminthofauna of Bombina bombina (Linnaeus, 1761) has been studied to an unequal degree in different parts of the habitat. Thus, it has been studied in more detail in the west of its range (in the countries of central and eastern Europe) and in less detail in the center (in Belarus and Ukraine). There were few data on helminths of this host in the east of its range (in Russia). For the first time, an inventory of the helminthofauna in B. bombina was carried out for populations in the Volga River Basin. The results of our own research are presented and supplemented with information from other authors. We summarized scattered data on helminths from 390 specimens of amphibians collected over more than 40 years in the territory of five regions: Kaluga and Samara regions, the Republics of Mordovia, Tatarstan and Bashkortostan. The helminthofauna includes 21 species from three classes: Trematoda (15), Chromadorea (5) and Clitellata (1). For each species, we give the systematic position, localization, places of detection, geographical distribution and characteristics of the life cycle. The leech Helobdella stagnalis (Linnaeus, 1758) was first recorded in the European fire-bellied toad in Europe. Four species of trematodes are new to this amphibian species in Russia: Haematoloechus abbreviatus (Bychowsky, 1932), Paralepoderma cloacicola (Luhe, 1909), larvae, Tylodelphys excavata (Rudolphi, 1803), larvae and Astiotrema monticelli (Stossich, 1904), larvae. Another species of trematode – Strigea strigis (Schrank, 1788), larvae – was first recorded in this host within the boundaries of the Volga Basin. A specific parasite is the trematode Haematoloechus abbreviatus (Bychowsky, 1932). The number and composition of the species of helminths of the European fire-bellied toad vary in different regions; the structure of the helminth fauna is generally stable and includes three groups of species: adult and larval stages of trematodes, adult nematodes-geohelminths. The results of the study create a database for further population studies and contribute to the development of ideas about the distribution and formation of the amphibian helminth fauna in Europe, Russia and the Volga Basin.

Morphological and molecular description of parasitic leeches (Annelida: Hirudinea) isolated from rice field of Bandar Anzali, North of Iran

The current study was performed to determine Hirudinea species diversity collected from rice fields of Guilan province from June 2012 to June 2020. This study reports the most recent information on leech species (Annelida, Clitellata) in this region. Morphological characters and DNA barcode analysis were used to identify the collected samples. According to the acquired results, there were two leech families in this zone (Glossiphoniidae and Hirundinidae). Based on morphological criteria 5 species of leech including Hirudo orientalis, Hirudo medicinalis, Hirudo verbana, Helobdella stagnalis and Placobdella costata belonging to 3 genera were identified. For the first time, Hirudo verbana which predominantly bred in leech farms and used as medicinal leech from southeastern Europe and Turkey, was reported in our study. The knowledge on leech fauna in Iran is incomplete. Therefore, more comparative studies based on molecular and morphological techniques should be conducted on different regions. This study was performed to identify the distribution of Hirudinida from Bandar Anzali's wetland of Guilan province, Iran using genetic sequence assessment.

Community metabarcoding uncovers vast diversity and a lack of barcode references for aquatic invertebrates in Carpathian spring fens

Recent studies on diversity of stream amphipods proposed that the Western Carpathians have served as an important glacial refugium of freshwater fauna. If this scenario is true, a considerably high molecular diversity can be expected in this biogeographic region also for other taxa. In our project, we aimed to uncover and characterize molecular diversity of benthic macroinvertebrate fauna of spring fens, a well studied and hence convenient model community. Using a DNA metabarcoding approach, we sequenced a fragment of the COI gene of pooled spring fen invertebrate communities from 21 localities in the Western Carpathians. The preliminary analysis of the sequences revealed a substantially higher amount of operational taxonomic units (OTUs), when compared to the number of taxa identified in the same spring fens based on morphological characters. The lack of reference sequences in public databases (Barcoding of Life Database, GenBank) for the majority of the detected OTUs indicates that the Western Carpathian region is not yet sufficiently covered by barcoding efforts, and suggests that there indeed may be a considerable unrecognized diversity of macrozoobenthos. However, most newly uncovered diversity is concentrated in a few taxa such as the dipteran families Tabanidae and Ceratopogonidae, annelid species (complexes) Eiseniella tetraedra and Helobdella stagnalis or the amphipod genus Gammarus. In the future, these findings will be the basis for several levels of research: detailed investigation of seemingly hyperdiverse taxa (phylogeography, phylogeny, reference coverage) and comparison of overall molecular diversity of these communities in the Western Carpathians and neighbouring Bohemian Massif, a region where we expect much lower diversity due to different biogeographic history.

Population structure and symbiotic relationships of the invasive speciesSinanodonta woodiana(Lea, 1834) in water bodies of Ukraine

Understanding the process of penetration and distribution of the invasive speciesSinanodonta woodianais important for predicting associated changes in biodiversity and the structure of freshwater communities. The biomass, density, age and sex structure of mollusk populations were analyzed. An increase in the size of Chinese pond mussels was noted after the introduction: the shell length of individuals from a pond (Romanivka village, 2017) was 24,2% more than of mollusks from the Velyka Repida river (Matroska village, 2004), and in 2019 it increased by another 14,7% (by 42,5% compared to the shell length of the mollusks from the Velyka Repida river). The body weight ofS. woodianafrom the river was 125,3 g, while in the pond there was a 2,13-fold increase in body weight in 2017, with a further increase in this indicator by another 23,6% in 2019 and another 37,7% in 2020. The relative number ofS. woodianaand native speciesUnio pictorumandAnodonta anatinain 2017 was 26,3%, 47,4% and 26,3%, in 2020 – 64,0%, 16,0% and 20,0% respectively. Ciliates of the genusConchophthirusandTrichodina,Aspidogaster conchicola,Helobdella stagnalis, larvae ofChironomussp. are in a symbiotic relationship withS. woodiana. The most commonConchophthirussp. – in 21,6% of individuals. Further spread ofS. woodianato the cold regions of Ukraine and the formation of new populations in the already developed regions should be expected.

Two new Helobdella species (Annelida Hirudinida Glossiphoniidae) from the Intermountain region of the United States, formerly considered as Helobdella stagnalis Linnaeus, 1758

Two new Helobdella species (Annelida Hirudinida Glossiphoniidae) from the Intermountain region of the United States, formerly considered as Helobdella stagnalis Linnaeus, 1758

Fauna, Spatial Distribution, and Ecological Peculiarities of Oligohaetes (Oligochaeta) and Leeches (Hirudinea) in the Ob’ River Basin

The fauna, spatial distribution, and ecological features of oligochaetes and leeches of reservoirs and watercourses of the Ob’ River basin (including Teletskoe Lake and Novosibirsk, Belovskoe, and Gilevskoe reservoirs) have been considered. Published and original data were summarized from 1903 to 2016. Various samplers were used: bottom grabs, scrapers and wash-off from the solid substrates. The assessment of the distribution of oligochaetes in the Ob’ River basin showed that oligochaeto and hirudofauna were formed mainly by eurybiont species, without significant zonal changes. The most common oligochaetes in the Ob’ River basin were Tubifex tubifex (Muller 1774), Limnodrilus hoffmeisteri Claparede 1862, Spirosperma ferox Eisen 1879, Lumbriculus variegatus (Muller 1773), Stylaria lacustris (Linnaeus 1767), Nais variabilis Piguet. 1906, Chaetogaster diaphanus (Gruithuisen 1828), leeches, Glossiphonia complanata (Linnaeus 1758), Helobdella stagnalis (Linnaeus 1758), and Erpobdella octoculata (Linnaeus 1758). These species were the key components of benthic biocenoses of the water bodies and watercourses of the Ob’–Irtysh interfluve. The species diversity of oligochaetes and leeches in the Ob’ River basin was much less than that in the large basins of Europe (Volga River) and Eastern Siberia (Lake Baikal) and was comparable with the fauna of certain regions of Europe and the Urals. The largest number of species of oligochaetes and leeches was noted in the well-studied basins of the Upper and Middle Ob’ River.

Broad geographic sampling and DNA barcoding do not support thepresence of Helobdella stagnalis (Linnaeus, 1758) (Clitellata: Glossiphoniidae) in North America.

The description of Helobdella stagnalis (Linnaeus, 1758) has emphasized the presence of a nuchal, chitinous scute located on the dorsal surface in the first third of the body as the diagnostic character for the species. Historically, identifications of species of Helobdella have relied heavily on this character and, as a result, Helobdella stagnalis has been reported from an inordinately broad geographic range, including Europe, Asia, Africa, North America, and South America. In addition to a few earlier investigations, a recent analysis showed that great genetic distances (orders of magnitude greater than previous estimations of intraspecific divergence in leeches) are present between scute-bearing specimens identified as H. stagnalis from Europe and North America, implying that H. stagnalis does not occur in North America. The present study expands the geographic boundaries of taxon sampling for both European and North American taxa, and re-examines the phylogenetic relationships and cytochrome c oxidase subunit I (COI) variation within scute-bearing species of the genus Helobdella. Our analyses include specimens putatively identified as "Helobdella stagnalis" from Sweden, Norway, Iceland, England, France, Italy, Slovenia, Turkey, Russia, and Iran, as well as numerous localities covering Canada and the USA. Our results corroborate previous studies in that European and west Asian specimens form a clade, including the neotype, which is separate from North American taxa. To alleviate future taxonomic confusion, we redescribe H. stagnalis and designate a neotype from the inferred type locality. The designation of a neotype stabilizes the taxonomy of scute-bearing leeches of the genus Helobdella and enables us to definitively correct erroneous identifications reported in previous studies. We also note that at least four lineages of scute-bearing, North American species of Helobdella lack formal descriptions.

Phylogenetic and morphological resolution of the Helobdella stagnalisspecies-complex (Annelida: Clitellata: Hirudinea).

The glossiphoniid freshwater leech, Helobdella stagnalis, was described by Linnaeus 1758 based on common European specimens. The presence of a brown, chitinous scute on the dorsal-anterior surface, as observed on leeches elsewhere in the world, has generally led to the classification of all scute-bearing members of the genus as H. stagnalis. Here we describe the morphology and behavior of the type species from Europe, and analyze H. stagnalis-like specimens collected worldwide. We present evidence for at least four distinct scute-bearing Helobdella species that can be morphologically resolved. Maximum Parsimony (MP) and Bayesian Inference (BI) analyses at the mitochondrial cytochrome c oxidase subunit I (COI) locus further supported this notion, with divergence values suggesting a mid-Miocene ancestor of this successful group of cosmopolitan hirudineans. New species, Helobdella echoensis nov. sp., Helobdella eriensis nov. sp., and Helobdella serendipitious nov. sp., are described, based on morphological, anatomical and molecular data. Current distribution patterns of Helobdella spp. suggest a robust, global dispersal mechanism, as well as local pockets of endemism.

Evidence for Substrate Influence on Artificial Substrate Invertebrate Communities.

Cobble baskets are frequently used as a tool to measure differences in benthic macroinvertebrate communities between waterbodies; however, underlying differences in substrate type may influence the resultant colonization of baskets, misrepresenting communities. This study tests the hypothesis that cobble basket placement influences the resulting benthic macroinvertebrate community. Cobble basket arrays (n = 4) were deployed in Dog Lake, Saskatchewan, in 2011 (97 d) and 2012 (95 d) on cobble habitats and soft or sandy substrates ∼100 m apart. Baskets placed on cobble substrate had significantly higher Shannon-Weaver diversity relative to those placed on soft substrate in both years, and higher % EPT (Ephemeroptera Plecoptera Trichoptera) in 2011, but total density was not significantly different. Nonmetric multidimensional scaling revealed that the community was different between both treatments, characterized by higher densities of Gammarus lacustris Sars in baskets placed on soft sediment in both years, higher densities of Aeshna sp. and Mystacides sp. on cobble substrate in 2011, and higher densities of Helobdella stagnalis (L.) and Glossophinia complanata (L.) on cobble substrate in 2012. The results were consistent with the hypothesis that baskets placed on cobble substrate versus soft substrate will result in differing community colonization. The resulting recommendation for monitoring and assessment using cobble baskets in lakes is that baskets be placed on comparable substrate type when comparing between lakes, and that cobble beds be chosen as a more appropriate substrate for deployment, as the added habitat complexity of baskets on soft sediment may act as an attractant and not reflect the true community composition of that habitat.

Helobdella blinni sp. n. (Hirudinida, Glossiphoniidae) a new species inhabiting Montezuma Well, Arizona, USA.

A new leech species Helobdella blinni sp. n., is described from Montezuma Well, an isolated travertine spring mound located in central Arizona, USA. In its native habitat, Helobdella blinni had been previously identified as Helobdella stagnalis (Linnaeus, 1758), which was later reclassified to Helobdella modesta (Verrill, 1872). Similar to the European Helobdella stagnalis and North American Helobdella modesta, Helobdella blinni has six pairs of testisacs, five pairs of smooth crop caecae, one lobed pair of posteriorly-directed crop caecae, one pair of eyes, a nuchal scute, and diffuse salivary glands. However, the pigmentation of this new species ranges from light to dark brown, unlike Helobdella modesta which tends to be light grey in color. Also, Helobdella modesta produces a clutch of 12-–35 pink eggs, whereas Helobdella blinni produces smaller clutches of white eggs (7–14, 0.5 ± 0.15 mm, N = 7) and consequently broods fewer young (1–14, 7 ± 3.3 mm, N = 97). Helobdella blinni are also able to breed year-round due to the constant warm water conditions in Montezuma Well. Their breeding season is not restricted by seasonal temperatures. These species are morphologically similar, however, comparing the COI mtDNA sequences of Helobdella blinni with sequences from nearby populations of Helobdella modesta and other Helobdella species from GenBank indicate that Helobdella blinni is genetically distinct from these other Helobdella populations.

Leeches (Hirudinea) in aquatic ecosystems of national park “Prielbrusye”

The article provides information about the fauna of leeches living in the various reservoirs on especially protected natural territories of the Federal state budget establishment “The National Park ‘Prielbrusye’”. Only 4 оf the 12 known in the Kabardino-Balkar Republic species of leeches inhabit the waters of the National Park ponds: Protoclepsis tessulata (O.F. Muller, 1774), Helobdella stagnalis (L., 1758), Haemopis sanguisuga (L., 1758) and Herpobdella octoculata (L, 1758). The author shows the location of leeches in the aquatic ecosystems. It is fond that their appearance in waters of the National Park “Prielbrusye” is mainly due to anthropogenic activities, particularly creation of artificial stagnant and partly stagnant reservoirs.

The present state of the leech fauna (Annelida, Hirudinea) in the Upper Irtysh cascade of water reservoirs.

Hirudinea is a small and ecologically important group of aquatic organisms. However, up to date, the leech fauna of Kazakhstan is poorly studied. The presence of large under-collected areas, such as the Upper Irtysh basin, makes biodiversity studies concerning these invertebrates from Kazakhstan relevant. In this paper, the latest information on species diversity of the freshwater hirudofauna of the Upper Irtysh cascade of water reservoirs, the Kazakhstan part of Irtysh River, is presented. It includes 10 free-living and parasitic species, of which 7 and 9 inhabit the Shulbinsk and the Bukhtarma reservoirs, respectively. These species belong to 2 orders, 3 families and 6 genera. The faunal list highlights four potentially new morphological species (Alboglossiphonia sp., Erpobdella sp., Piscicola sp. 1 and Piscicola sp. 2). Besides them, another three species Erpobdella vilnensis, Helobdella stagnalis and Theromyzon tessulatum recorded for the first time in the area. The exact systematic position is stated for all leech taxa. Each species from the list accompanied with information on taxonomic synonymy, data on its geographic distribution, and brief summary of morphological and ecological characteristics.